| # yallist | |
| Yet Another Linked List | |
| There are many doubly-linked list implementations like it, but this | |
| one is mine. | |
| For when an array would be too big, and a Map can't be iterated in | |
| reverse order. | |
| [](https://travis-ci.org/isaacs/yallist) [](https://coveralls.io/github/isaacs/yallist) | |
| ## basic usage | |
| ```javascript | |
| var yallist = require('yallist') | |
| var myList = yallist.create([1, 2, 3]) | |
| myList.push('foo') | |
| myList.unshift('bar') | |
| // of course pop() and shift() are there, too | |
| console.log(myList.toArray()) // ['bar', 1, 2, 3, 'foo'] | |
| myList.forEach(function (k) { | |
| // walk the list head to tail | |
| }) | |
| myList.forEachReverse(function (k, index, list) { | |
| // walk the list tail to head | |
| }) | |
| var myDoubledList = myList.map(function (k) { | |
| return k + k | |
| }) | |
| // now myDoubledList contains ['barbar', 2, 4, 6, 'foofoo'] | |
| // mapReverse is also a thing | |
| var myDoubledListReverse = myList.mapReverse(function (k) { | |
| return k + k | |
| }) // ['foofoo', 6, 4, 2, 'barbar'] | |
| var reduced = myList.reduce(function (set, entry) { | |
| set += entry | |
| return set | |
| }, 'start') | |
| console.log(reduced) // 'startfoo123bar' | |
| ``` | |
| ## api | |
| The whole API is considered "public". | |
| Functions with the same name as an Array method work more or less the | |
| same way. | |
| There's reverse versions of most things because that's the point. | |
| ### Yallist | |
| Default export, the class that holds and manages a list. | |
| Call it with either a forEach-able (like an array) or a set of | |
| arguments, to initialize the list. | |
| The Array-ish methods all act like you'd expect. No magic length, | |
| though, so if you change that it won't automatically prune or add | |
| empty spots. | |
| ### Yallist.create(..) | |
| Alias for Yallist function. Some people like factories. | |
| #### yallist.head | |
| The first node in the list | |
| #### yallist.tail | |
| The last node in the list | |
| #### yallist.length | |
| The number of nodes in the list. (Change this at your peril. It is | |
| not magic like Array length.) | |
| #### yallist.toArray() | |
| Convert the list to an array. | |
| #### yallist.forEach(fn, [thisp]) | |
| Call a function on each item in the list. | |
| #### yallist.forEachReverse(fn, [thisp]) | |
| Call a function on each item in the list, in reverse order. | |
| #### yallist.get(n) | |
| Get the data at position `n` in the list. If you use this a lot, | |
| probably better off just using an Array. | |
| #### yallist.getReverse(n) | |
| Get the data at position `n`, counting from the tail. | |
| #### yallist.map(fn, thisp) | |
| Create a new Yallist with the result of calling the function on each | |
| item. | |
| #### yallist.mapReverse(fn, thisp) | |
| Same as `map`, but in reverse. | |
| #### yallist.pop() | |
| Get the data from the list tail, and remove the tail from the list. | |
| #### yallist.push(item, ...) | |
| Insert one or more items to the tail of the list. | |
| #### yallist.reduce(fn, initialValue) | |
| Like Array.reduce. | |
| #### yallist.reduceReverse | |
| Like Array.reduce, but in reverse. | |
| #### yallist.reverse | |
| Reverse the list in place. | |
| #### yallist.shift() | |
| Get the data from the list head, and remove the head from the list. | |
| #### yallist.slice([from], [to]) | |
| Just like Array.slice, but returns a new Yallist. | |
| #### yallist.sliceReverse([from], [to]) | |
| Just like yallist.slice, but the result is returned in reverse. | |
| #### yallist.toArray() | |
| Create an array representation of the list. | |
| #### yallist.toArrayReverse() | |
| Create a reversed array representation of the list. | |
| #### yallist.unshift(item, ...) | |
| Insert one or more items to the head of the list. | |
| #### yallist.unshiftNode(node) | |
| Move a Node object to the front of the list. (That is, pull it out of | |
| wherever it lives, and make it the new head.) | |
| If the node belongs to a different list, then that list will remove it | |
| first. | |
| #### yallist.pushNode(node) | |
| Move a Node object to the end of the list. (That is, pull it out of | |
| wherever it lives, and make it the new tail.) | |
| If the node belongs to a list already, then that list will remove it | |
| first. | |
| #### yallist.removeNode(node) | |
| Remove a node from the list, preserving referential integrity of head | |
| and tail and other nodes. | |
| Will throw an error if you try to have a list remove a node that | |
| doesn't belong to it. | |
| ### Yallist.Node | |
| The class that holds the data and is actually the list. | |
| Call with `var n = new Node(value, previousNode, nextNode)` | |
| Note that if you do direct operations on Nodes themselves, it's very | |
| easy to get into weird states where the list is broken. Be careful :) | |
| #### node.next | |
| The next node in the list. | |
| #### node.prev | |
| The previous node in the list. | |
| #### node.value | |
| The data the node contains. | |
| #### node.list | |
| The list to which this node belongs. (Null if it does not belong to | |
| any list.) | |